How to say "adversary" in Japanese

• 敵てきJLPT N3approx.Common
  nounThe broad, general word: an enemy, opponent, or rival in war, competition, or personal conflict. When you just mean 'adversary' with no special nuance, this is the usual choice.
  ある男おとこを判断はんだんするには、その人ひとの友人ゆうじんによるのと同様どうように敵てきによって判断はんだんするのがいいだろう。↗

  You shall judge of a man by his foes as well as by his friends.
• 敵かたきJLPT N1approx.
  noun (suffix), nounThe same kanji with a native reading, typically a personal enemy or rival you feel a grudge against. Less common than てき and more emotionally charged.
• 敵対勢力てきたいせいりょく
  nounAn opposing force, faction, or power rather than an individual — the word for hostile groups, as in political or military opposition, not for a single personal enemy.
• 反対者はんたいしゃ
  nounReally 'opponent' in the sense of someone who is against a plan, proposal, or view — a dissenter or objector. It implies disagreement rather than enmity, so it fits 'adversary' only loosely.
• 対戦相手たいせんあいて
  no-adjectiveThe opponent in a game, match, or contest — 'the other side' you compete against. It carries no hostility, so it suits 'adversary' only in the sporting or competitive sense.

For 'adversary', 敵（てき） is the general word; 敵（かたき） is the same word with an often personal, grudge-tinged nuance; 敵対勢力 is an opposing force or faction; 反対者 a dissenter; 対戦相手 an opponent in a game or match.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 敵てきopponent
• 敵かたきrival
• 敵対勢力てきたいせいりょくadversary
• 反対者はんたいしゃfoe
• 対戦相手たいせんあいてopponent